Zenbexus-led combination nabs FDA’s first CELMoD therapy approval in multiple myeloma
The FDA approved iberdomide (Zenbexus, Bristol Myers Squibb) as the first cereblon E3 ligase modulation therapy for relapsed or refractory multiple myeloma, in combination with daratumumab and hyaluronidase-fihj (Darzalex Faspro) and dexamethasone. In the phase 3 EXCALIBER-RRMM trial, MRD-negative complete response at any time was 41% vs 21% in the comparator arm.
How this was made

The 30-second read
Why it matters
The approval is anchored to a phase 3, two-stage EXCALIBER-RRMM trial and reports a higher MRD-negative complete response rate versus a comparator arm, supporting a differentiated efficacy narrative for a new mechanism class.
Market read
A first-in-class CELMoD approval with MRD-negative complete response outperformance is a concrete regulatory catalyst for the sponsor’s multiple myeloma pipeline and commercialization expectations.
What to watch
The article notes fatal adverse reactions in the iberdomide arm and boxed warnings (embryo-fetal toxicity, thromboembolism), which could affect prescribing comfort, label uptake, and near-term commercialization trajectory.
Background
The FDA granted accelerated approval for iberdomide (Zenbexus) as the first CELMoD therapy in relapsed or refractory multiple myeloma, based on MRD-negative complete response results.
Ticker impact
FDA approved iberdomide (Zenbexus, Bristol Myers Squibb) in multiple myeloma, including MRD-negative complete response data from EXCALIBER-RRMM.
Likely positive bias for BMY shares on approval headlines, with follow-through dependent on uptake and competitive positioning.
The article is a first FDA approval for a CELMoD therapy in relapsed or refractory multiple myeloma, with a clear efficacy endpoint (MRD-negative complete response) and accelerated approval framing, which typically drives re-rating expectations for the sponsor.
Market effects
Strengthens the competitive narrative for cereblon E3 ligase modulation (CELMoD) combinations in multiple myeloma and may pressure incumbents’ positioning around MRD endpoints.
Primarily US-focused sentiment given FDA action, with potential spillover to global oncology peers via read-across on MRD-driven adoption.
New class validation can influence global multiple myeloma treatment standards and subsequent trial designs worldwide.
Counterpoint
Despite approval, accelerated pathways and MRD endpoints may not fully translate into durable survival benefit, limiting how much the market should extrapolate immediately.
Key entities
- DrugIberdomide (Zenbexus)
CELMoD therapy approved by FDA in combination with daratumumab and hyaluronidase-fihj plus dexamethasone for adults with multiple myeloma after at least one prior line.
- CompanyBristol Myers Squibb
Co-developer/sponsor of Zenbexus (iberdomide) referenced as part of the approved regimen.
- Clinical trialEXCALIBER-RRMM trial
Phase 3, two-stage study used for FDA decision-making, reporting MRD-negative complete response at any time.
- RegulatorFDA
Granted accelerated approval for the first CELMoD therapy in relapsed or refractory multiple myeloma based on MRD-negative complete response.



